1. Field of the Invention
The present invention relates to a switch device of a portable flashlight and more particularly relates to an improvement of the operation and durability in a switch device of the portable flashlight containing two bulbs which can be turned on and off.
2. Statement of the Prior Art
The conventional portable flashlight comprises, for example, as shown in FIG. 5, an outer casing C which is made of plastic, etc., two bulbs LA, LB, a dry battery B, a switch S and a lighting circuit W. The casing C is provided with the switch S which turns on and off and opens and closes the lighting circuit W. The lighting of the bulbs LA and LB can be turned on and off by the thumb of an operator while he holds the casing C.
Such well known switch of the portable flashlight can be slide along the casing C so that the height of the projection portion of the switch "S" becomes small, since it is difficult to operate the switch by the thumb of the operator while he holds the casing C if the height H of the projection portion becomes large.
The above mentioned conventional switch device has the function which turns on and off the two bulbs LA and LB, and therefore, it includes a number of parts and is somewhat complicated in construction. This slide-type arrangement has a weak point of durability, such that the bulbs LA and LB cannot be turned on an doff smoothly and reliably since sliding friction between the individual parts becomes strong and the individual parts becomes abrasive.
Furthermore, the slide-type arrangement has a disadvantage in operation, such that it is difficult to slide the switch due to sands the like attached onto the surface of the casing C since it requires a large space for sliding on the surface of the casing C.